August 27 2021Vol 70No 34 - PDF document

1 1150 August 27, 2021Vol. 70No. 34 New CO
1150 August 27, 2021Vol. 70No. 34 New COVID-19 Cases and Hospitalizations Among Adults, by Vaccination Status — New York, May 3–July 25, 2021 Eli S. Rosenberg, PhD 1,2 ; David R. Holtgrave, PhD 2 ; Vajeera Dorabawila, PhD 1 ; MaryBeth Conroy, MPH 1 ; Danielle Greene, DrPH 1 ; Emily Lutterloh, MD 1,2 ; Bryon Backenson, MS 1,2 ; Dina Hoefer, PhD 1 1 ; Ursula Bauer, PhD 1 ; Howard A. Zucker, MD, JD 1 On August 18, 2021, this report was posted as an MMWR Early Release on the MMWR website ( https://www.cdc.gov/mmwr ) . Data from randomized clinical trials and real-world obser - vational studies show that all three COVID-19 vaccines cur - rently authorized for emergency use by the Food and Drug Administration* are safe and highly effective for preventing ( 1 , 2 ). Studies of vaccine effectiveness (VE) for preventing new infections and hospitalizations attributable to SARS-CoV-2, the virus that causes COVID-19), particularly as the B.1.617.2 (Delta) variant has become predominant, are limited in the United States ( 3 ). In this study, the New York State Department of Health linked statewide immunization, laboratory testing, and hospitalization databases for New York to estimate rates of new laboratory- confirmed COVID-19 cases and hospitalizations by vaccination status among adults, as well as corresponding VE for full vaccina - tion in the population, across all three authorized vaccine prod - against new COVID-19 cases for all adults declined from 91.7% to 79.8%. During the same period, the overall age-adjusted VE against hospitalization was relatively stable, ranging from 91.9% to 95.3%. Currently authorized vaccines have high effectiveness against COVID-19 hospitalization, but effectiveness against new cases appears to have declined in recent months, coinciding with the Delta variant’s increase from to % 0;&#x.5 0;80% in the U.S. region that includes New York and relaxation of masking and physical distancing recommendations. To reduce new COVID-19 cases and hospitalizations, these findings support the implementation of a layered approach centered on vaccination, as well as other prevention strategies such as masking and physical distancing. Four databases (the Citywide Immunization Registry, New York State Immunization Information System, Electronic Clinical Laboratory Reporting System, and Health Electronic surveillance-based cohort of adults aged 18 years residing in New York by using individual name-based identifiers, date of birth, and zip code of residence. The Citywide Immunization Registry and the New York State Immunization Information System are used to collect and store all COVID-19 provider vaccination data for persons residing in New York City and the As of the publication date of this report, COVID-19 vaccines by Pfizer- BioNTech, Moderna, and Janssen (Johnson & Johnson) have been authorized by the Food and Drug Administration under Emergency Use Authorization. rest of the state, respectively (excluding selected settings such as Veterans Affairs and military health care facilities); persons were considered fully vaccinated 14 days after receipt of the final vaccine dose. † System collects all reportable COVID-19 test results (nucleic acid amplification test [NAAT] or antigen) in New York ( 4 ); a new COVID-19 case was defined as the receipt of a new positive SARS-CoV-2 NAAT or antigen test result, but not within 90 days of a previous positive result. HERDS includes a statewide, daily electronic survey of all inpatient facilities in New York; new admissions with a laboratory-confirmed COVID-19 diagnosis are entered into HERDS daily by trained hospital staff members. After a period of phased COVID-19 vaccine eligibility based on age, occupation, setting, or comorbidities beginning in December 2020

2 , all New York residents aged 60 ye
, all New York residents aged 60 years were eligible for vaccination by March 10, 2021; eligibility was adults aged 18 years by April 6. § To allow time for a large portion of vaccinated persons to achieve full immunity, this study was restricted to the week beginning May 3 through the week beginning July 19, 2021. Breakthrough infections were defined as new cases among persons who were fully vaccinated on the day of specimen collection. Hospitalizations among persons with breakthrough infection were defined as new hospital admissions among persons fully vaccinated on the reporting day. The total adult state population that was fully vaccinated and unvaccinated ¶ was assessed for each day and stratified by age group (18–49 years, 50–64 years, and 65 years). Persons who were partially vaccinated were excluded from analyses. For each week and age group, the rates of new cases and Morbidity and Mortality Weekly Report US Department of Health and Human Services/Centers for Disease Control and Prevention hospitalizations were calculated among fully vaccinated and unvaccinated persons, by respectively dividing the counts for each group by the fully vaccinated and unvaccinated person- days in that week. Age-adjusted VE each week was estimated † Final dose was the second dose for Pfizer-BioNTech and Moderna vaccines, first dose for Janssen vaccine. § https://www.governor.ny.gov/news/governor-cuomo-announces-new-yorkers- 30-years-age-and-older-will-be-eligible-receive-covid-19 ¶ The total adult state population that was unvaccinated was calculated as the total U.S. Census population, minus fully or partially vaccinated persons. Persons who were partially vaccinated were defined as those who initiated a vaccine series but did not complete it or were within 14 days after completion. August 27, 2021Vol. 70No. 34 as the population-weighted mean of the age-stratified VE.** The interval between completing vaccination and positive SARS-CoV-2 test result date was summarized using the median, interquartile range (IQR), and percentage tested 7 days from being fully vaccinated. †† The ratio of hospitalizations to cases was computed for each vaccination group to understand the relative severity of cases. Statistical testing was not performed because the study included the whole population of interest and was not a sample. By July 25, 2021, a total of 10,175,425 (65.8%) New York adults aged 18 years were fully vaccinated; 1,603,939 (10.4%) were partially vaccinated. Among fully vaccinated adults, 51.3% had received Pfizer-BioNTech, 39.8% had received Moderna, and 8.9% had received Janssen (Johnson & Johnson) vaccines. During May 3–July 25, a total of 9,675 new cases (1.31 per 100,000 person-days) occurred among fully vacci - nated adults, compared with 38,505 (10.69 per 100,000 per - son-days) among unvaccinated adults (Table). Most (98.1%) new cases among fully vaccinated persons occurred 7 days after being classified fully vaccinated (median = 85 days; IQR=58–113). During May 3–July 25, case rates among fully vaccinated persons were generally similar across age groups, as **For both outcomes, VE at each week and age group was calculated as 1-(Rate vaccinated / Rate unvaccinated ). The percentage tested 7 days from being fully vaccinated was included to inform possible undiagnosed infection before full vaccination was achieved. were case rates among unvaccinated persons, declining through the end of June before increasing in July (Figure 1). Weekly estimated VE against new laboratory-confirmed infection during May 3–July 25 for all age groups generally declined, ranging from 90.6% to 74.6% for persons aged 18–49 years, 93.5% to 83.4% for persons aged 50

3 0;64 years, and 92.3% to 88.9% for pers
0;64 years, and 92.3% to 88.9% for persons aged 65 years. During May 3–July 25, the overall, age-adjusted VE against infection declined from 91.7% to 79.8% ( Figure 1 ) ( Table ). A total of 1,271 new COVID-19 hospitalizations (0.17 per 100,000 person-days) occurred among fully vaccinated adults, compared with 7,308 (2.03 per 100,000 person-days) among unvaccinated adults ( Table ). Hospitalization rates generally declined through the week of July 5, but increased the weeks of July 12 and July 19, and were higher among fully vaccinated and unvaccinated persons aged 65 years compared with younger age groups (Figure 2). Age group–specific estimated VE against hospitalization remained stable, ranging from 90.8% to 97.5% for persons aged 18–49 years, from 92.4% to 97.0% for persons aged 50–64 years, and from 92.3% to 96.1% for persons aged 65 years. During May 3–July 25, the overall, age-adjusted VE against hospitalization was generally stable from 91.9% to 95.3% ( Figure 2) ( Table). The ratio of hospitalizations to cases was mod - erately lower among fully vaccinated (13.1 hospitalizations per 100 cases) compared with unvaccinated (19.0 hospitalizations per 100 cases) groups. TABLE. Vaccination coverage, new COVID-19 cases, and new hospitalizations with laboratory-confirmed COVID-19 among fully vaccinated and unvaccinated adults, and estimated vaccine effectiveness — New York, May 3–July 25, 2021 Week starting Population* New cases † New hospitalizations § Average no. fully vaccinated ¶ Average no. unvaccinated Full vaccination coverage, % Fully vaccinated Unvaccinated Estimated vaccine effectiveness, % Fully vaccinated Unvaccinated Estimated vaccine effectiveness, % No. Rate* No. Rate* No. Rate* No. Rate* May 3 6,255,275 5,367,527 40.4 700 1.60 7,387 19.66 91.7 154 0.35 1,478 3.93 95.3 May 10 6,948,727 4,938,120 44.9 589 1.21 5,839 16.89 92.7 149 0.31 1,145 3.31 95.0 May 17 7,641,098 4,642,464 49.4 555 1.04 4,106 12.63 91.9 134 0.25 968 2.98 96.2 May 24 8,222,099 4,444,612 53.1 431 0.75 2,757 8.86 92.0 140 0.24 748 2.40 93.8 May 31 8,691,229 4,289,385 56.2 364 0.60 2,092 6.97 91.6 87 0.14 549 1.83 95.1 Jun 7 9,034,873 4,226,865 58.4 341 0.54 1,504 5.08 89.7 95 0.15 448 1.51 93.3 Jun 14 9,272,840 4,165,878 59.9 340 0.52 1,233 4.23 87.9 88 0.14 324 1.11 91.9 Jun 21 9,516,612 4,022,274 61.5 396 0.59 1,201 4.27 85.8 60 0.09 283 1.01 94.6 Jun 28 9,747,395 3,913,256 63.0 535 0.78 1,421 5.19 83.8 69 0.10 288 1.05 93.9 Jul 5 9,911,987 3,870,504 64.1 928 1.34 2,223 8.20 82.4 72 0.10 270 1.00 94.4 Jul 12 10,034,269 3,818,600 64.8 1,703 2.42 3,242 12.13 78.2 89 0.13 340 1.27 94.8 Jul 19 10,135,322 3,742,197 65.5 2,793 3.94 5,500 21.00 79.8 134 0.19 467 1.78 95.3 Total — — — 9,675 1.31 38,505 10.69 — 1,271 0.17 7,308 2.03 — Population sizes fully vaccinated and unvaccinated were computed daily. For display purposes, the average populations fully vaccinated and unvaccinated are shown for each week. Rate calculations were conducted using daily population sizes and are expressed per 100,000 person-days. Persons partially vaccinated were excluded from analyses. † New cases were defined as a new positive SARS-CoV-2 nucleic acid amplification test or antigen test result, not within 90 days of a previous positive result, reported to the Electronic Clinical Laboratory Reporting System, which collects all reportable COVID-19 test results in New York. § New hospitalizations were determined by a report of a hospital admission with a confirmed COVID-19 diagnosis, entered into the Health Electronic Response Data System, which includes a statewide, daily electronic survey of all inpatient facilities in New York. ¶ Persons were determined to be fully vaccinated following 14 days after final vaccine

4 -series dose receipt, per the Citywide I
-series dose receipt, per the Citywide Immunization Registry and the New York State Immunization Information System, which collect and store all COVID-19 vaccine receipt data by providers for persons residing in New York City and the rest of New York, respectively. 1152 August 27, 2021Vol. 70No. 34 Discussion In this study, current COVID-19 vaccines were highly effective against hospitalization (�VE 90%) for fully vacci - nated New York residents, even during a period during which prevalence of the Delta variant increased fr% t;&#xo 00;om in the U.S. region that includes New York, societal public health restrictions eased, §§ and adult full-vaccine coverage in §§ https://covid.cdc.gov/covid-data-tracker/#variant-proportions FIGURE 1. New COVID-19 cases among fully vaccinated and unvaccinated adults, vaccine coverage, and estimated vaccine effectiveness, by age — New York, May 3–July 25, 2021 Cases per 100,000: fully vaccinatedCases per 100,000: unvaccinatedCases per 100,000: all personsFully vaccinated coverageEstimated vaccine eectiveness Support Width OptionsPage wide = 7.5”QuickStats = 5.0”1½ columns = 4.65”1 column = 3.57” Cases per 100,000 Week May Age = 18–49 years % Vaccine coverage and eectiveness Cases per 100,000Week May Age = 50–64 years 0102030405060708090100 % Vaccine coverage and eectiveness Cases per 100,000 Week MayAge 65 years% Vaccine coverage and eectiveness Cases per 100,000Week MayAll adults aged 18 years % Vaccine coverage and eectiveness August 27, 2021Vol. 70No. 34 New York neared 65%. However, during the assessed period, rates of new cases increased among both unvaccinated and fully vaccinated adults, with lower relative rates among fully vac - cinated persons. Moreover, VE against new infection declined from 91.7% to 79.8%. To reduce new COVID-19 cases and hospitalizations, these findings support the implementation of a layered approach centered on vaccination, as well as other prevention strategies. FIGURE 2. New hospitalizations with laboratory-confirmed COVID-19 among fully vaccinated and unvaccinated adults, vaccine coverage, and estimated vaccine effectiveness, by age — New York, May 3–July 25, 2021 Hospitalizations per 100,000: fully vaccinatedHospitalizations per 100,000: unvaccinatedHospitalizations per 100,000: all personsFully vaccinated coverageEstimated vaccine eectiveness Support Width OptionsPage wide = 7.5”QuickStats = 5.0”1½ columns = 4.65”1 column = 3.57” Hospitalizations Week May New hospitalizations: age = 18–49 years % Vaccine coverage and eectiveness Hospitalizations per 100,000Week May New hospitalizations: age = 50–64 years 0102030405060708090100 % Vaccine coverage and eectiveness Hospitalizations per 100,000 Week MayNew hospitalizations: age 65 years% Vaccine coverage and eectiveness Hospitalizations per 100,000Week MayNew hospitalizations: all adults aged 18 years % Vaccine coverage and eectiveness 171614131110875421 0369121518171614131110875421 0369121518171614131110875421 0369121518171614131110875421 1154 August 27, 2021Vol. 70No. 34 Summary What is already known about this topic? Real-world studies of population-level vaccine effectiveness against laboratory-confirmed SARS-CoV-2 infection and COVID-19 hospitalizations are limited in the United States. What is added by this report? During May 3–July 25, 2021, the overall age-adjusted vaccine effectiveness against hospitalization in New York was relatively stable (91.9%–95.3%). The overall age-adjusted vaccine effectiveness against infection for all New York adults declined from 91.7% to 79.8%. What are the implications for public health practice? These findings support the implementation

5 of multicomponent approach to controll
of multicomponent approach to controlling the pandemic, centered on vaccination, as well as other prevention strategies such as masking and physical distancing. The findings from this study are consistent with those observed in other countries. Israel has reported 90% VE for the Pfizer-BioNTech vaccine against hospitalization; however, a decline in VE against new diagnosed infections occurred dur - ing June 20–July 17 (decreasing to )( 5 ). Another study in the United Kingdom found higher VE against infection with the Delta variant for Pfizer-BioNTech (88%), which was lower than VE against the B.1.1.7 (Alpha) variant (94%) ( 6 ). The factors driving the apparent changes in VE, including variations by age, are uncertain. Changes in immune protec - tion from current vaccine product dosing regimens are under investigation, ¶¶ with additional doses being considered ( 7 ). Increased Delta variant viral load might underpin its increased transmissibility and could potentially lead to reduced vaccine- induced protection from infection ( 8 ). Further, variations from clinical trial findings could be because the trials were conducted during a period before the emergence of new variants and when nonpharmaceutical intervention strategies (e.g., wearing masks and physically distancing) were more stringently implemented, potentially lessening the amount of virus to which persons were exposed. Other factors that could influence VE include indi - rect protective effects of unvaccinated persons by vaccinated persons and an increasing proportion of unvaccinated persons acquiring some level of immunity through infection ( 9 ). The findings in this report are subject to at least six limi - tations. First, although limiting the analysis period to after universal adult vaccine eligibility and age stratification likely helped to reduce biases, residual differences between fully vaccinated and unvaccinated groups have the potential to reduce estimated VE. Second, the analysis excluded partially vaccinated persons, to robustly assess VE for fully vaccinated ¶¶ https://www.medrxiv.org/content/10.1101/2021.07.28.21261159v1 compared with that of unvaccinated persons. A supplementary sensitivity analysis that included partially vaccinated persons as unvaccinated yielded conservative VE for laboratory-confirmed infection (declining from 88.7% to 72.1%) and for hospitaliza - tions (ranging from 89.7% to 93.0%). Third, exact algorithms were used to link databases; some persons were possibly not linked because matching variables were entered differently in the respective systems. Fourth, this study did not estimate VE by vaccine product, and persons were categorized fully vaccinated at 14 days after final dose, per CDC definitions; however, the Janssen vaccine might have higher efficacy at 28 days.*** Given that Janssen vaccine recipients accounted for 9% of fully vaccinated persons and the observed time period from full vaccination to infection (median 85 days), this would minimally affect the findings. Fifth, information on reasons for testing and hospitalization, including symptoms, was lim - ited. However, a supplementary analysis found that among 1,271 fully vaccinated adults and 7,308 unvaccinated adults, 545 (42.9%) and 4,245 (58.1%), respectively, were reported to have been admitted for COVID-19 by hospital staff members using nonstandardized definitions. A sensitivity analysis of hospitalization VE limited to those admitted for COVID-19, found similar results (VE range=93.9%–97.4%), suggesting that the extent of bias was limited. Finally, data were too sparse to reliably estimate VE for COVID-19-related deaths. This study’s findings suggest currently available vaccines have high effectiveness for preventing laboratory-confirmed

6 SARS-CoV-2 infection and COVID-19 hosp
SARS-CoV-2 infection and COVID-19 hospitalization. However, VE against infection appears to have declined in recent months in New York, coinciding with a period of eas - ing societal public health restrictions ††† and increasing Delta variant circulation ( 8 ). These findings support a multipronged approach to reducing new COVID-19 hospitalizations and cases, centered on vaccination, and including other approaches such as masking and physical distancing. Acknowledgments Steven Davis, Rebecca Hoen, New York State Department of Health; Citywide Immunization Registry Program, New York City Department of Health and Mental Hygiene. Corresponding author: Eli Rosenberg, eli.rosenberg@health.ny.gov . New York State Department of Health; 2 University at Albany School of Public Health, State University of New York, Rensselaer, New York. All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed. *** https://www.fda.gov/media/146338/download https://coronavirus.jhu.edu/data/state-timeline/new-confirmed-cases/ new-york/205 August 27, 2021Vol. 70No. 34 References 1.Food and Drug Administration. COVID-19 vaccines. Silver Spring, MD: US Department of Health and Human Services; Food and Drug Administration; 2021. Accessed July 29, 2021. https://www.fda.gov/ emergency-preparedness-and-response/coronavirus-disease-2019- covid-19/covid-19-vaccines . Pilishvili T, Fleming-Dutra KE, Farrar JL, et al.; Vaccine Effectiveness Among Healthcare Personnel Study Team. Interim estimates of vaccine effectiveness of Pfizer-BioNTech and Moderna COVID-19 vaccines among health care personnel—33 U.S. sites, January–March 2021. MMWR Morb Mortal Wkly Rep 2021;70:753–8. PMID:34014909 https://doi.org/10.15585/mmwr.mm7020e2 3.CDC. COVID-19 vaccine breakthrough case investigation and reporting. Atlanta, GA: US Department of Health and Human Services, CDC; 2021. Accessed July 29, 2021. https://www.cdc.gov/vaccines/covid-19/ health-departments/breakthrough-cases.html Rosenberg ES, Dufort EM, Blog DS, et al.; New York State Coronavirus 2019 Response Team. COVID-19 testing, epidemic features, hospital outcomes, and household prevalence, New York State—March 2020. Clin Infect Dis 2020;71:1953–9. PMID:32382743 https://doi. org/10.1093/cid/ciaa549 5.Israel Ministry of Health. Decline in vaccine effectiveness against infection and symptomatic illness. Jerusalem, Israel: Israel Ministry of Health; 2021. Accessed July 29, 2021. https://www.gov.il/en/departments/ news/05072021-03 . Lopez Bernal J, Andrews N, Gower C, et al. Effectiveness of Covid-19 vaccines against the B.1.617.2 (Delta) variant. N Engl J Med 2021. Epub July 21, 2021. PMID:34289274 https://doi.org/10.1056/ NEJMoa2108891 Kamar N, Abravanel F, Marion O, Couat C, Izopet J, Del Bello A. Three doses of an mRNA Covid-19 vaccine in solid-organ transplant recipients. N Engl J Med 2021. Epub June 23, 2021. PMID:34161700 https://doi. org/10.1056/NEJMc2108861 8.Brown CM, Vostok J, Johnson H, et al. Outbreak of SARS-CoV-2 infections, including COVID-19 vaccine breakthrough infections, associated with large public gatherings—Barnstable County, Massachusetts, July 2021. MMWR Morb Mortal Wkly Rep 2021l;70:1059–62. PMID:34351882 https://doi.org/10.15585/mmwr.mm7031e2 Patel MK, Bergeri I, Bresee JS, et al. Evaluation of post-introduction COVID-19 vaccine effectiveness: summary of interim guidance of the World Health Organization. Vaccine 2021;39:4013–24. PMID:34119350 https://doi.org/10.1016/j.vaccine.2021.05.099 US Department of Health and Human Services/Centers for Disease Control and Prevention Morbidity and Mortality Weekly R